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05/01/2004 06:37:14 PM · #1
I'm wondering if anyone can tell me if my DoF will increase for macro shots if I upgrade from my Canon G3 to a Canon Digital Rebel. I know I need a fast lense, and it could be expensive, but before I spend all that money I just want to make sure I can really increase my DoF. I am a honeybee researcher, and I can't get what I want from my G3. In this picture I took a few days ago, you can see part of the bee, but the ant attacking it is out of focus, as is parts of the bee, and this was on a very bright day.

//www.pbase.com/image/28466111

Thanks much
05/01/2004 06:41:01 PM · #2
To increase your DOF, the last thing you need is a fast lens. To increase the DOF you need to stop down the lens = increase the aperture number. So what's the point of buying a fast lens?

Increase the DOF:
* wideangle lens a pre
* stop the lens down to F11-F22
* focal point relatively far away, 2/3 of the focussed area is in front and 1/3th behind the point of focus



Message edited by author 2004-05-01 18:46:28.
05/01/2004 06:43:15 PM · #3
The maximum aperture on the G3 is f8.

With a digital SLR you will have more choices for aperture depending on the lenses you choose. Maximum (smallest opening) apertures can reach f32 and beyond.

Message edited by author 2004-05-01 18:44:05.
05/01/2004 06:46:01 PM · #4
Hi Jim..

From the looks of that photo, the the DOF is really small. The smaller the apeture, the larger the DOF. I'm not really sure how manual the G3 is, but if you make the apeture smaller (by increasing the f/stop number), the DOF should increase. The offshoot of that (which is especially relevant to macro shooting) is that less light will be available. So you will have to lower your shutter speed too, which can cause motion blur, etc, if you dont use a tripod.

In the case that you know all this anyway... A DSLR lense generally lets more light in, and has a much larger f/stop number. For example the smallest apeture I can get on my nikon 5400 is 7.9. The smallest apeture i can get on my D70 with 18-70mm, 3.5-4.5 lens is 22. You'll also find that the lenses themselves have more blades on the irises, so they produce more pleasing blurred artifacts in the background if you have a small DOF.

-Dan
05/01/2004 06:51:07 PM · #5
Originally posted by cpanaioti:

The maximum aperture on the G3 is f8.

With a digital SLR you will have more choices for aperture depending on the lenses you choose. Maximum (smallest opening) apertures can reach f32 and beyond.


The CCD/CMOS size plays a role there.
F8 on a G3 is like F16 to F22 DOF-wise on a 300D, because the G3 CCD is so much smaller. Compared to the lenses available for a 300D the G3 has an extreme wideangle zoom lens. The more you move to wideangle the more DOF you get.

Most lenses don't go beyond F22 I believe and on digital it doesn't matter if they do because of refraction problems.


05/01/2004 07:21:47 PM · #6
Thanks much for the quick replies.

So, forget what my neighbor said about a fast lense. I need a wide angle macro lense. If I am concentrating on Macros, is there a marked difference between the Canon and Nikon competitor in the 1000 dollar range?

Also, what kind of lense should I buy that will get me those nice macros, as in brand and model?

Thanks
05/01/2004 07:32:18 PM · #7
Originally posted by Azrifel:



Most lenses don't go beyond F22 I believe and on digital it doesn't matter if they do because of refraction problems.


Both lenses I have go well beyond f22. One to 32 and the other to 45. I haven't seen any distortions or other problems etc.

Message edited by author 2004-05-01 19:33:16.
05/01/2004 07:45:59 PM · #8
I meant diffraction, couldn't get the right word.
05/01/2004 07:56:45 PM · #9
Is there a macro lense that can go down to f/32 or more?
05/01/2004 08:42:04 PM · #10
Originally posted by JimB:

Thanks much for the quick replies.

So, forget what my neighbor said about a fast lense. I need a wide angle macro lense. If I am concentrating on Macros, is there a marked difference between the Canon and Nikon competitor in the 1000 dollar range?

Also, what kind of lense should I buy that will get me those nice macros, as in brand and model?

Thanks


Jim, given that you are a honeybee researcher and that you do a lot of Macro work it would be wise to get a good Macro lens. Canon has a super Macro lens that can give life size (1:1) to 5x life size. Check out the following link //www.usa.canon.com/html/eflenses/lenses/mp_e65_28/mp_e65_28.html
You can use the Diguital Rebel or 10D or any other Canon DSLR.
05/01/2004 08:56:41 PM · #11
And by the way, Jim you got some fantastic Macro shots! If you get that Canon super Macro lens you'll make lots of people on here green with envy... ;-)
05/01/2004 09:11:19 PM · #12
Thanks for the link and complement. It says f/2.8, which is much less than what I have with the G3, and the sample picture doesn't have much DoF.

There must be something out there?

Thanks and regards.
05/01/2004 10:22:08 PM · #13
In most cases, the aperture listed is for wide-open shots to demonstrate how fast the lens is. For example the Canon kit lens is listed at f/3.5-5.6, which means f/3.5 at 18mm wide open and f/5.6 at 55mm wide open. The aperture on that lens can actually go down to about f/32 I believe. The 65mm macro lens mentioned by doctornick will go down to f/16. There's a good review of it here.
05/01/2004 10:25:43 PM · #14
Originally posted by JimB:

Thanks for the link and complement. It says f/2.8, which is much less than what I have with the G3, and the sample picture doesn't have much DoF.

There must be something out there?

Thanks and regards.


Jim I think you are misunderstanding something, when a lens is referred as being f/2.8 it means that it's it's maximum aperture, its minimum aperture is usually in the range of f/22 to f/32. You can step down the lens when shooting to get more DOF. In terms of Canon equipment that mpe65 is the ultimate. Doesn't get better than that.
05/01/2004 10:30:19 PM · #15
doctornick... that lens is apparently faster than you are- beat ya' to it. ;-)

Message edited by author 2004-05-01 22:30:58.
05/01/2004 10:42:29 PM · #16
Thanks for all your replies, and sorry for my misunderstanding. I'll try to absorb this.

Thank you all very much.

Very best
Jim
05/01/2004 10:48:28 PM · #17
Scalvert, this is what I'm looking for. Do you think I can get these kinds of shots with a Canon Digital Rebel and that lense? I'm willing to blow my honey account if so, it would be worth a couple hundred stings.

Kind regards
05/01/2004 10:55:20 PM · #18
Originally posted by JimB:

Scalvert, this is what I'm looking for. Do you think I can get these kinds of shots with a Canon Digital Rebel and that lense? I'm willing to blow my honey account if so, it would be worth a couple hundred stings.

Kind regards


Absolutely! If you use the ring lite flash you'll have total control over any bug you shoot. The lens is $829.95 at B & H
//www.bhphotovideo.com/bnh/controller/home;jsessionid=AUiImc1bF7!-128875411?O=productlist&A=details&Q=&sku=183199&is=USA
05/01/2004 11:10:08 PM · #19
I can't speak from experience since I don't own the lens, but there are many insect macros on the luminous-landscape article I listed... all taken with that lens and an older Canon DSLR. They look good to me. If your budget allows, I don't think there's a better alternative available. If you need another opinion, I'd PM one of our resident bug macro gurus... this means you, Jacko!
05/01/2004 11:16:49 PM · #20
Thanks, I haven't posted for months, but I recognise the fearsome name of Jacko!! Perhaps he'll give his two bits.

But thank you so much, those that have posted.
05/02/2004 07:16:57 AM · #21
JimB- you might save some buck by figueing out precisely what you need for your bee research shots before buying. Here are a couple of websites that show you how to calculate DoF-
DoFMaster
Focus Pocus
05/02/2004 10:52:44 AM · #22
Excuse my minor point here, but the Canon MPE 65 millimetre lens will not give you great depth of field! The greater the magnification that you get, the less the depth of field. Also as a point of note, to get those kinds of magnification with that lens you need to be quite close. One of the 180 millimetre macro lenses would be more suitable.

One other point about this, you will either need a good flashgun or a tripod.
05/02/2004 11:01:22 AM · #23
It's not a minor point, I just stumbled on it myself when reading up on it. I see a Canon 100mm f/2.8 is half the price, and stops down to f/32 rather than just f/16. I will have to look at your 180 recommendation.

But the C 100mm only magnifies to 1:1. Can anyone direct me to some macros taken with this lense?
05/02/2004 12:08:14 PM · #24
You may want to check out this article by Mark Plonsky. Most of his (amazing) macro stuff is shot with a PowerShot G1 or G3. This is one instance where the small sensor size of a non-DSLR is a benefit (since it has the side effect of increased DOF).

Unfortunately, shallow DOF is just the reality of shooting macros. And as others have mentioned, just because a lens on a DSLR can go to /32 doesn't mean you should, since really tiny apertures (large -numbers) result in reduced quality due to the effects of diffraction.

Message edited by author 2004-05-02 15:07:18.
05/02/2004 12:19:52 PM · #25
Macro lens reviews and examples:

100mm f2.8
MP-E 65mm
180mm plus other review links at bottom and an insect gallery
another for the MP-E 65mm

That should get you started.
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